The medium and heavy duty truck and semi-trailer industry has long employed frame brackets (often referred to as "hanger brackets") for connecting at least one end of a suspension system to the frame member of the vehicle to which the suspension is to be attached. Such brackets come in a wide variety of styles and designs, but in virtually every instance of a recognized or commercially acceptable bracket there must be employed various welds to maintain the integrity of the bracket. Such welds have been found safe and effective for their intended purpose and have served the industry well. However, welding is often labor intensive or, if done with robotics, can require a significant capital investment. In short, they are expensive. Moreover, welds, while safe if properly made, have, by their nature, a start and stop point which are often located at the highest point of stress and thus are subject to the potential, at these points, of the possibility of fatigue crack initiation.
Certain well accepted and conventional hanger brackets have often needed to employ, for adequate attaching capabilities, an "L" shaped mounting mechanism which gloves one side (usually the outboard side) and bottom of the vehicle's frame rail as the attaching surfaces. This "L" shaped mounting mechanism automatically sets the height of the bracket and prohibits any higher mounting by its inherent "L" shape and glove-like construction.
FIG. 1 illustrates a typical example of a well known right (R) and left (L) side pair of frame brackets for connecting a liftable or non-liftable beam type suspension (not shown) at one end to the right and left side frame rails, respectively, of a vehicle. The other end of the beams are conventionally connected to their respective frame rail, usually by an air bellows of known construction. An example of such a suspension employing this bracket is disclosed in U.S. Pat. No. 5,403,031. As can be seen, the mechanism for connecting the bracket to its frame rail is an "L" shaped member having a vertical flange A and a horizontal flange B. Flange B dictates the limit on the distance upwardly that brackets R and L may be located on the frame rails. Indeed, since flange B is designed to fit snugly against the underside of the frame rail, flange B, usually by design, determines the precise distance the suspension can be located below the frame rail. No flexibility is allowed the installer (OEM or otherwise) who may face several different frame rail configurations, such as straight frame rails, as well as so-called "drop belly" frames.
With still further reference to FIG. 1, brackets R and L at their various seams (e.g. C, D, E, etc.) are held together by welds. While proven safe and effective, these welds are generally not accessible by robotics, and the construction is highly labor intensive. Moreover, as illustrated by distance "d", orifices F and G's center line H, and thus the center lines of the beams or control arms (not shown) which extend into them in a conventional fashion, is offset outboard (usually a distance "d" of 1/4 to 1/2 inches) of center line I of the frame rail of the vehicle when snugly fit to "L" shaped member A, B. This widens the suspension. It, of course, would be more desirable to narrow the distance between right and left side control arms. The less space consumed by the suspension, the easier it is to accommodate other equipment required on the vehicle where envelopes of compliance are often quite small.
In view of the above, it is apparent that there exists a need in the art for a substantially weld free bracket assembly which, in addition, provides for a flexible choice of installation heights, as well as the reduction or elimination of the outboard offset distance "d" as described above.
It is a purpose of this invention to fulfill these and other needs in the art more apparent to the skilled artisan once given the following disclosure.